A gate valve with wedge-shaped disks has a cylindrical thrust bolt between its disks, which rest in the longitudinal axis of the connections when the valve is closed. The force needed to close the valve is transmitted to the disks through the shaft, through a compression screw extending from the shaft, and through the thrust bolt. The disks are uniformly distributed over two sealing surfaces at each side of the housing. Since the shaft of the known wedge-disk gate valve exhibits preliminary travel, the force of compression must be released through the compression screw and thrust bolt when the shaft is lifted to facilitate opening the valve. Nevertheless, the opening moment must be 1.5 times the closure moment to ensure smooth opening of the valve.
German Patent Application No. P 32 06 190.0 describes a gate valve with wedge-shaped disks supported against each other on at least two resilient rings that can be mutually displaced axially. These rings are positioned at the level of the disk sealing surfaces. This design diminishes the forces exerted on the sealing surfaces when the valve is opened.
The present invention is intended as a modification of the position of the disks in a gate valve of the aforesaid type that will allow the valve to be operated with lower opening forces.